Lemon Upside-Down Pie with Plums

Ingredients:

• 1 and 3/4 cups sugar
• 4 plums, cut into 1cm thick slices (about 0.6 kg)
• 1 and 3/4 cups premium flour
• 1 teaspoon baking powder
• 0.5 tsp of soda
• 0.5 tsp salt
• 110 g unsalted butter, room temperature
• 2 large eggs
• 1 tsp vanilla extract
• 3/4 cup milk
• 1/4 cup sour cream
• 1.5 tsp finely grated lemon zest (1 lemon)

Preparation:

1. Preheat oven to 190°C.
2. In a 10-inch ovenproof skillet, combine 3/4 cup sugar and 1 1/2 tablespoons water; stir until the mixture resembles wet sand. Cook over medium heat, gently swirling the skillet occasionally but not stirring with a spoon, until the caramel turns a light amber color, about 5 minutes. Remove from heat and arrange the plums in a circle on top of the caramel; set the skillet aside.
3. In a bowl, combine the flour, baking powder, baking soda, and salt. In a large bowl, beat the butter and the remaining 1 cup sugar with a mixer on medium speed until light and fluffy, about 3 minutes. Add the eggs one at a time, beating after each addition, then beat in the vanilla. In a small bowl, combine the milk, sour cream, and lemon zest. Reduce the mixer speed to low; add the flour mixture to the butter mixture in three additions, alternating with the milk mixture, beginning and ending with the flour, and knead the dough.
4. Pour the batter over the plums and spread it evenly. Place the pan in the oven and bake until the pie is golden brown and a toothpick inserted into the center comes out clean, about 50 minutes. If the pie is browning too quickly, cover it with foil. Let it rest for 15 minutes, then invert it onto a plate and let it cool completely.